Heel release ski binding



April 23, 1957 N. T. KNAUF 2,789,827

HEEL RELEASE SKI BINDING Filed May 16, 1955 2 Sheets-Sheet 1 37 3INVENTOR NICHOLAS TKNAUF ATTORNEYS April 23, 1957 -N. T. KNAUF ,7

HEEL RELEASE SKI BINDING Filed May 16, 1955 2 Sheets-Sheet 2 ATTORNEYSUnitedStates Patento HEEL RELEASE SKI BINDING Nicholas T. Knauf,Chilton, Wis.

Application May 16, 1955, Serial No. 508,541

2 Claims. (Cl. 28011.35)

My invention appertains to ski bindings, and more particularly to asafety heel release for the ski binding that will hold the boot and heelfirmly to the ski but will automatically release upon strains orstresses which are greater than those'which can be safely borne by theskier.

In recent years there has been a series of developments in safety skibindings due to the fact that the conventional fixed type bindings,while being ideal for the various maneuvers required in good skiing, areextremely dangerous when spills and falls occur. Therefore, attemptshave been made in the past to provide for releasable bindings so thatthe skier may free himself from a ski in a spill and thus avoid seriousinjury.

In my prior U. S. Patent No. 2,682,416, issued to me June 29, 1954, Ihave shown and described an excellent means for firmly securing the bootto the ski but also providing for the release of the boot whensulficient force is exerted upon my safety binding. .This particularbinding is of the front assembly type and releasably secures the toe ofthe boot to the ski, and while this binding will release upon sufficientforce in almost any direction, it is conceivable that it might notrelease quick enough upon a direct upward movement of the heel of theboot away from the ski. While the straight upward movement of the heelaway from the ski would rarely occur without other movement of the boot,'it has, nevertheless, been found desirable to provide some sort of arelease that would release and free the boot from the ski when force isapplied to the heel in an upward direction.

tlt is, therefore, a primary object of my present invention to provide aski binding having a safety heel release that will operate to releasethe boot from the ski when the skiers heel is raised beyond apredetermined amount from the ski with a force that would otherwiseprove serious or cause injury.

Another important object of my present invention is to provide a safetyheel release having a movable tripout piece that will free the boot fromthe ski when the heel is also dangerously and forcibly moved laterallyin relation to the ski.

A further object of my invention is the provision of a safety heelrelease which is adjustable to a fine degree of precision so that itwill not release under the usual forces encountered in the normal skiingprocedure and minor spills, but will immediately and automaticallyrelease when stresses and strains are encountered of sufficient force toinjure the skien,

-A still further object of my invention is to provide an automaticallyreleasable heel ski binding which is incorporated in the heel tensioningstrand or cable and which can be used, not only with present safetydevices associated with the toe irons or the toes of the boots withoutinterference, but which also can be easily used with the majority ofconventional type fixed ski 'bind ings and toggle mechanisms locatedforward of the toe of the boot without alteration thereof.

2,789,827 Patented Apr. 23, 1957 A salient object of my inventionresides in the fact that I have provided a releasable heel ski bindingof comparatively simple construction which can be simply andinexpensively made and incorporated in presently used tensioning strandsor heel cables, and which is simple and easy to use by skilled skiers ornovices alike and is dependable when used for downhill skiing, racing,jumping or the like.

With the above and other objects in view which will more readily appearas the nature of the invention is better understood, the same consistsin the novel construction, combination and arrangement of partshereinafter more fully described, illustrated and claimed.

One preferred and practical embodiment of my invention is shown in theaccompanying drawings, in which:

'Figure 1 is a side elevational view of my novel heel release shown inconjunction with my safety front assembly which is more fully shown anddescribed in my prior U. S. Patent No. 2,682,416,. the ski boot beingshown firmly but releasa'bly held to the ski;

Figure 2 is an enlarged fragmentary side elevational view of my novelsafety heel release similar to Figure 1 of the drawings but showing therelease adjusted so that the heel may be raised slightly before it isreleased;

Figure 3 is a fragmentary rear elevational view illustrating details ofmy heel release binding;

Figure 4 is a fragmentary rear elevational view simi lar to Figure 3 ofthe drawings 'but showing the tripout piece in its released position andabout to free the heel tensioning strand or cable;

Figure 5 is a horizontal section taken through my novel heel release,the section being taken on the line 5-5 of Figure 3 of the drawings andlooking in the direction of the arrows;

Figure 6 is a rear elevational view in perspective of the body piece andtrip-out piece of my heel release;

Figure 7 is a top plan View of the preferred form of my adjusting meansfor the release cable, certain parts being broken away and in section toillustrate various details of construction, the section beingrepresented by the line 7-7 of Figure 2 of the drawings and looking inthe direction of the arrows; and

Figure 8 is a top plan view similar to Figure 7 of the drawings butillustrating a modified form of my adjusting means for the cable and theheel release.

Referring now to the drawings in detail, wherein similar referencecharacters designate corresponding parts throughout the several views,the letter H generally indicates one type of my improved safety heelrelease bind ing and the same is shown associated with a safety frontrelease assembly F to hold the boot B firmly but releasably to the skiS.

As previously explained, my heel release binding H may be utilizedeither with safety front assemblies or with the conventional fixed typeassemblies, but I prefer to utilize the same in conjunction with mysafety front assembly F shown and described in my prior U. S. Patent No.2,682,416. Obviously, the construction of the front assembly F forms noparticular part of my present invention and any means may be utilized tohold the toe 10 of the boot B to the ski S. Y

My novel heel release binding H includes, broadly, the release mechanism11, the torsion spring and latch assembly 12, a release cable 13 havingone end 14 looped about the spring 12 and having itsother end 15adjustably secured to the ski 5.. The release mechanism 11 firmly andreleasably holds the ends of the heel tensioning strands or cables 16and 17 together.

When my novel heel release H is utilized with a safety front assemblysuch as the one illustrated, the heel cables 16 and 17 are adjustablysecured to the sides of the ski S, as shown in Figure 1 of the drawings,and this is accomplished by means of a bracket 18 which receives thethreaded member 19 which is attached to the end of the cable 16 and thecable and threaded member is adjusted by means of the Hex. bolt head 20.The cable 17 is secured to the other side of the ski S in exactly thesame manner and both may be provided with a cable holddown 21. if myheel release H is to be utilized with a conventional fixed type binding,it is obvious that the inner ends 19 of the cables 16 and 17 may beextended forward of the toe to be secured to a toggle arrangement or thelike without affecting my heel release assembly in any manner. However,regardless of the type of bindings used, the ends 22 and 23,respectively, of the cables 16 and 117 have swedged or otherwise securedthereto the end balls 24 and 25. Although not necessary, I may provide anumber of additional balls 26 which are loosely secured to the cableends inwardly of the balls 24 and 25, respectively, and this arrangementmerely provides an additional adjusting means between the cables and therelease 11 as will be readily apparent as the description proceeds.

Referring now more particularly to Figure 6 of the drawings, it can beseen that the release mechanism 11 includes the body piece 27 and thetrip-out piece 28 which is pivotally secured at one end to the body 27by means of the shouldered rivet 2?. The body 27 may be stamped from asingle piece of metal and the lower tab 30 is bent upward U-shaped asshown and is provided with a central longitudinally extending slot 31. Ialso provide an upstanding lug 32 which receives the main body portion33 of the spring 12. One side of the body piece 27 is provided with asmall notch 34 which is adapted to receive the offset end 36 of thespring 12. The lower leg 37 of the spring extends laterally across theslot 31 within the U-shaped tab 30, and it should be here noted that theleg 37 of the spring 12 is urged towards the leg 33 and that the loopedend 14 of the release cable 13 extends into the slot 31 and is fittedover the leg 37 of the spring. The other side of the body 27 is formedwith an enlarged cutout or slot 39, the lower end of which slantsangularly and downwardly as at 40. Trip-out piece 28 is provided with akeeper notch 41 which receives the upturned latch end 42 of the springleg 37 and this piece is normally held in the position illustrated inFigures 1, 2 and 3 of the drawings. It should be noted that the innerend of the trip-out piece 28 is provided with a cooperating angularlyand downwardly extending surface 43 which, in the normal operativeposition, is opposite the angular extending end 40 of the body 27 andthe two cooperate to act as camming surfaces to facilitate the quickmovement of the trip-out piece 23 from its closed full 'line position toits released dotted line position as indicated by the arrow in Figure 4of the drawings.

A salient feature of my invention resides in the novel means foradjustably securing the trip-out cable 13 to the ski so that it may movea pre-determined distance before the trip-out mechanism 11 can beactuated, thus allowing some freedom and upward movement of heel ifdesired. This adustment includes a longitudinally extending bracket 4dwhich is firmly secured to the ski S in rear of the heel releasemechanism 11. One end of the bracket 44 is provided with a verticallyextending piece 45 which is provided with a threaded hole to adjustablyreceive an externally threaded tube 46, and the tube may be movedbackward and forward in relation to the piece 45 and secured in place bythe lock nut 47. The cable 13 is passed through the hole 48 provided inthe angularly extending piece 4-9 back through the tube as and the cableend 15 is provided with a button or abutment which is swedged orotherwise secured thereto. Thus the distance between the tube 46 and thecable end 15 may be adjusted as desired.

Obviously, this adjustment of the release cable 13 may be accomplishedby any number of ways and I have illustrated one modified form in Figure8 of the drawings. In this arrangement the cable 13 is received in thebrackof 4-4 in the same manner as illustrated in Figure 7. However, thetube 46 is eliminated and an adjustable device 51 is substitutedtherefor. This device includes an internal member 52 threadably receivedin the outer member 53, and by threading the member 51 in one directionit will grip the cable 13, while turning the member 52 in the oppositedirection will loosen the device on the cable 13, and, therefore, anadjustable stop may be had at any desired spot between the verticalplate 45 and the button 54.

in utilizing my novel heel release binding H, the toe 10 of the boot Bis firmly secured to the ski S by means of my front assembly F and thecables 16 and 17 are adjusted in the present instance by means of theHex. Sill so that the ball ends may be brought together as bet- 1%)!shown in Figures 2 to 5 of the drawings. Again it is to be rememberedthat the cable 16 and 17 may extend entirely forward of the toe as inthe conventional type of fixed binding. In any event, the ball ends 22and 23 of the cables 16 and 17, respectively, are received in the slot39 of the body piece 27. It makes no difference whether the heel cables16 and 17 are adjusted so that the balls 24 and are received in the slotor so that any one of the loosely fitted balls 26 are received in thecutout or slot 39. However, with the ball ends in place the trip-outpiece 28 is pivoted downwardly until the keeper 41 is caught by thelatch end 42 of the spring 12. As the spring 12 is of the torsion type,the trip-out piece 28 will normally be held in the position illustratedin Figure 3, and inasmuch as the upper portion of the slot 39 is of asmaller Width than the diameter of the balls, the cable ends 22 and 23will be firmly held in the release mechanism 11. The loop 14 of therelease cable 13 is, of course, secured over the leg 37 of the springand the cable extends downwardly therefrom through the slot 31 of thetab to the bracket 44. The tube 44 is then adjusted to allow for thedesired movement of the heel 55 before the release mechanism willoperate. Obviously, the distance between end 15 of the release cable 13and the tube 46 may be adjusted so that when heel 55 of the boot B isheld in firm contact with the ski S by the ten sion strand or cables theend 15 will abut the tube 46 and the release will operate immediately,or it may be adjusted as shown in Figures 1 and 2 to allow for a slightupward movement of the heel 55.

In any event, should the forward movement of the ski be abruptlystopped, such as may be caused by digging in of the ski tip due to softheavy snow and the like, the forward motion of the skiers body willcause the heel 55 to be raised in the direction of the arrow of Figure 2of the drawings until the button on the end 15 of the release cable 13strikes the tube 45. Further dangerous and excessive force will thencause the release cable 13 to pull downwardly on the latch leg 37 of thespring 1?. where the latch 42 will be disengaged from the keeper 41.Additional movement then causes the cable end 23, aided by the cammingsurfaces 4 b and 53, to pivoi the trip-out piece 28 to its dotted lineposition in the direction of the arrow of Figure 4 of the drawings andthe cable 17 will free itself from the release mechanism 11. Obviously,it is not necessary that cable 16 free itself from the release mechanism11, but it is free to move out of slot 39 when necessary. Although Imay, if

- desired, fix the end 22 of the cable 16 to the body piece 27, I wouldprefer, for adjustment pulposes, that both ends 22 and 23 of the cables16 and 17 be free to move in and out of the slot 39.

From the foregoing it is believed that the features and advantages of myinvention will be readily apparent to those skilled in the art, and itwill, of course, be understood that changes in the form, proportion andminor details of construction may be resorted to without departing fromthe spirit of the invention or the scope of the appended claims.

I claim:

1. In a ski-binding of the type wherein a tensioned strand memberanchored to the ski encircles the heel of the boot, a safety heelrelease mechanism comprising; a divided heel element formed in saidtensioned strand member including, an identical abutment formed on theend of each portion of said divided heel element, a body piece havingone end secured to the ski, said body piece being formed with anelongated transverse slot opening out on one side thereof, said slotbeing defined by parallel surfaces one of which extends angularly awayfrom the other surface adjacent the open end thereof, said end strandportions of said divided heel element being received in said slotadjacent said boot heel, the end abutment of each end portion being of alarger diameter than the inner width of said slot, a trip-out piecepivoted at one end to said body piece adjacent said slot, said trip-outpiece having the surface adjacent said open end of said slot formed as acooperating angle surface with said angle surface of said slot, andlatching means for said trip-out piece adapted in one position to holdsaid tripout piece over the open end of said slot and to secure the saidstrand end portions therein and adapted in another position to releasesaid trip-out piece upon a pre-determined force to allow said piece topivot away from said slot opening and to release said strand endportions.

2. In a ski-binding of. the type wherein a tensioned strand memberanchored to the ski encircles the heel of the boot, a safety heelrelease mechanism comprising; a divided heel element formed in saidtensioned strand member including an identical abutment formed on theend of each portion of said divided heel element, a body piece beingformed with an elongated slot opening out on one side thereof, said endstrand portions of said divided heel element being received in said slotadjacent said boot heel, the end abutment of each end portion being of alarger diameter than the width of said slot, a trip-out piece pivoted atone end to said body piece adjacent said slot, a latching means for saidtrip-out piece including, a torsion spring having one leg received in akeeper formed in said trip-out piece a release cable having one endsecured to said ski and the other end secured to said spring leg, saidlatching means torsion spring being so constructed and arranged as tohold said trip-out piece in one position over the open end of said slotand to secure the said strand end portions therein and adapted inanother position to release said trip-out piece upon a pre-deterrninedforce or pull of said release cable on said spring leg to allow saidpiece to pivot away from said slot opening and to release said strandend portions.

References Cited in the file of this patent UNITED STATES PATENTS1,621,604 Ruggles Mar. 22, 1927 2,323,723 Mushet July 6, 1943 2,517,486Hewett Aug. 1, 1950 2,618,487 Gould Nov. 18, 1952 2,673,743 Gould Mar.30, 1954 2,682,416 Knauf June 29, 1954 2,722,449 Harley Nov. 1, 1955FOREIGN PATENTS 843,364 France Mar. 27, 1939 37,983 Sweden Mar. 5, 1913

